Re: [Qemu-devel] [PATCH 2/6] target/m68k: Optimize the partset instruction using deposit_i32()

[Richard Henderson]

On 3/9/19 4:34 PM, Philippe Mathieu-Daudé wrote:
>      case OS_BYTE:
> -        tcg_gen_andi_i32(reg, reg, 0xffffff00);
>          tmp = tcg_temp_new();
>          tcg_gen_ext8u_i32(tmp, val);

Might as well elide this as well.

> -        tcg_gen_or_i32(reg, reg, tmp);
> +        tcg_gen_deposit_i32(reg, tmp, reg, 8, 24);
>          tcg_temp_free(tmp);
>          break;
>      case OS_WORD:
> -        tcg_gen_andi_i32(reg, reg, 0xffff0000);
>          tmp = tcg_temp_new();
>          tcg_gen_ext16u_i32(tmp, val);

Likewise.

> -        tcg_gen_or_i32(reg, reg, tmp);
> +        tcg_gen_deposit_i32(reg, tmp, reg, 16, 16);
>          tcg_temp_free(tmp);
>          break;